In many localities, utility cables, particularly fiber optic cables employed for carrying telecommunications traffic, are buried directly along side a railroad track or highway. Generally, land use planning guidelines require that roads and railroad tracks be buffered on opposite sides with unoccupied land for reasons of safety and for esthetics. Utilities, and particularly, telecommunications carriers find it advantageous to bury their cables along on such land, given that such land is otherwise vacant and there are often few barriers to burying cables underneath such lands.
Utility cable burial along side a road or railroad track poses a safety risk to utility technicians who must to maintain or repair such cables during intervals of vehicle and rail traffic, respectively. In practice, most of the noise associated with an oncoming vehicle will not be heard upstream of the vehicle. Hence, utility technicians working in the vicinity of a utility right-of-way parallel to a transportation pathway will not hear oncoming vehicles that pose a threat to worker safety. For that reason, the utility undertaking the maintenance or repair typically hires one or more workers whose sole responsibility is to flag any oncoming road or rail traffic to warn of the presence of utility technicians. In most instances, the entity responsible for the roadway or railroad track will insist on having its personnel flag down oncoming traffic. Consequently, the utility undertaking repairs of its buried cable must first make arrangements to obtain the necessary personnel to flag down oncoming traffic. Inevitably, the utility will bear the cost of such personnel who can be expensive.
There are electronic devices in the art for automatically detecting the presence of an oncoming vehicle, particularly a railroad train, by sensing the presence of the vibration created along the railroad track by the train. However, these devices are not believed effective alert individuals working along a railroad track of the presence of an oncoming train.
Thus, there is a need for a technique for providing a warning to personally alert individual utility technicians of the presence of an oncoming vehicle, (e.g., a motor vehicle or railroad train) traveling on a transportation pathway parallel to a utility cable right-of-way.